Field of the Invention
The present invention relates to an air conditioner for a vehicle, and more particularly, to an air conditioner for a vehicle, which includes and evaporator and a storage tank storing a heat carrier exchanging heat with the evaporator so as to accumulate cold air or warm air.
Background Art
Recently, releases of hybrid cars or idle-stop cars have been rapidly increased as measures for improvement of fuel efficiency and as countermeasures on environmental pollution according to the exhaust gas emission regulations.
In case of the hybrid cars or the idle-stop cars, engines are automatically stopped when they come to stop due to waiting for signal, but they have a problem in that a compressor for a cooling cycle connected to the engine is stopped, and it causes a lack of a heat source for cooling, and thus, comfort inside the cars is deteriorated.
In order to solve the above problem, there have been many studies on an air conditioner which has a cold storage function inside the air conditioner or has a battery separately mounted so as to operate the air conditioner by the battery when the engine is stopped for a long time.
FIG. 1 is a schematic diagram of a conventional air conditioner for a vehicle.
As shown in FIG. 1, the conventional air conditioner for the vehicle includes an air-conditioning case 1, an air blower 2a, an evaporator 3a and a heater core 4, a temperature-adjusting door 5, and a storage tank 6.
The air-conditioning case 1 includes: an indoor and outdoor air converting door 1a mounted at an inlet for allowing an inflow of the indoor air and the outdoor air; and vents 1e, 1f and 1g mounted at an outlet and adjusted in the degree of opening by doors 1b, 1c and 1d. The air blower 2a is mounted at the inlet of the air-conditioning case 1, and the evaporator 3a and the heater core 4 are mounted in an inside flow channel of the air-conditioning case 1 in order.
The temperature-adjusting door 5 adjusts the degree of opening of a cold air passageway P1 and a warm air passageway P2 of the air-conditioning case 1, and the storage tank 6 is arranged at the downstream side of the evaporator 3a in order to accumulate cold air passing through the evaporator 3a. 
In the conventional air conditioner for the vehicle having the above structure, when a compressor (not shown) interlocked with the engine is operated, a refrigerant cycle including the evaporator 3a is also operated and the indoor air and the outdoor air introduced through the indoor and outdoor air converting door 1a are heat-exchanged in the evaporator 3a and discharged to the vents 1e, 1f and 1g, and during the above process, cold air heat-exchanged in the evaporator 3a is accumulated in the storage tank 6.
In the above state, in the case of the hybrid cars which stop operation of the engine for a short period of time like when the cars stop by waiting for signal or like when the cars are stopped due to traffic jam, the operation of the refrigerant cycle is stopped by the stop of the engine, and thus, cold air accumulated in the storage tank 6 is discharged so as to cool the inside of the car.
The conventional air conditioner for the vehicle needs the storage tank 6 of a large capacity in order to sufficiently carry out the cold storage function. However, if capacity of the storage tank 6 is increased, the air conditioner occupies a large installation space and the entire load and volume of the air conditioner are also increased.